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v3.20.4

Share-Based Payment Plans (Details) $ / shares in Units, shares in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 CAD ($) shares | Dec. 31, 2019 CAD ($) shares $ / shares | Dec. 31, 2018 CAD ($) shares | Feb. 29, 2016 shares
Disclosure of terms and conditions of share-based payment arrangement [line items] |  |  |  |
Expense from cash-settled share-based payment transactions in which goods or services received did not qualify for recognition as assets |  | $ 25,000,000 |  |
Expense from equity-settled share-based payment transactions in which goods or services received did not qualify for recognition as assets |  | 24,000,000 |  |
Cumulative change in compensation expense |  | 1,000,000 |  |
Executive officers |  |  |  |
Disclosure of terms and conditions of share-based payment arrangement [line items] |  |  |  |
Number of share options granted (in shares) | shares | 0.7 |  |  |
Weighted average exercise price of share options granted in share-based payment arrangement | $ 9.17 | $ 5.65 | $ 7.45 |
PSUs and RSUs |  |  |  |
Disclosure of terms and conditions of share-based payment arrangement [line items] |  |  |  |
Performance period | 3 years |  |  |
Vesting period | 3 years |  |  |
Par value per share | $ / shares |  | $ 8.29 |  |
Compensation expense (reversal) | $ 15,000,000 | $ 19,000,000 | 8,000,000 |
PSUs |  |  |  |
Disclosure of terms and conditions of share-based payment arrangement [line items] |  |  |  |
Performance period | 3 years |  |  |
RSUs |  |  |  |
Disclosure of terms and conditions of share-based payment arrangement [line items] |  |  |  |
Vesting period | 3 years |  |  |
DSUs |  |  |  |
Disclosure of terms and conditions of share-based payment arrangement [line items] |  |  |  |
Compensation expense (reversal) | $ 1,000,000 | 2,000,000 | 0 |
Stock Options |  |  |  |
Disclosure of terms and conditions of share-based payment arrangement [line items] |  |  |  |
Number of shares authorized (in shares) | shares |  |  |  | 16.5
Stock Options | Executive officers |  |  |  |
Disclosure of terms and conditions of share-based payment arrangement [line items] |  |  |  |
Vesting period | 3 years |  |  |
Compensation expense (reversal) | $ 2,000,000 | $ 1,000,000 | $ 1,000,000 |
Number of share options granted (in shares) | shares |  | 1.4 | 0.7 |

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- Definition The amount of expense arising from cash-settled share-based payment transactions in which the goods or services received did not qualify for recognition as assets. [Refer: Expense from share-based payment transactions in which goods or services received did not qualify for recognition as assets] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_112_c&doctype=Standard -URIDate 2019-03-27 + Details
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